1. Field of the Invention
The present invention is generally related to a cooling water distribution system for a marine propulsion device and, more particularly, to a water system that is configured to remove debris from the vicinity of a drain opening and, in some circumstances, from the region proximate the surface of water stored in a container of the water system.
2. Description of the Related Art
Those skilled in the art of marine propulsion system are familiar with many different configurations in which water is conducted through an internal combustion engine and through one or more containers that temporarily retain the water in thermal communication with other components of the marine propulsion system before directing the water back to a body of water from which it was originally drawn. In many cases, the water is temporarily held in a container within the driveshaft housing of the marine propulsion device, such as an outboard motor, as it is directed downwardly through the driveshaft housing and back to the body of water.
U.S. Pat. No. 4,776,820, which issued to Mapes on Oct. 11, 1988, discloses a bilge water pump mechanism for an outboard motor cowl. It describes a pump mechanism continuously operable by the engine of an outboard motor for discharging water that collects by seepage or leakage into the engine cowl. The pump mechanism includes an inlet conduit having an inlet end positioned closely adjacent to the bottom of an inclined channel formed in the lower section of the engine cowl and an outlet conduit having an outlet end positioned exteriorly of the cowl. A filter disposed in the inlet conduit removes debris from the water and protects the pump mechanism and the bracket mounted to the engine block holds the inlet end of the inlet conduit closely adjacent to the bottom of the channel.
U.S. Pat. No. 5,579,727, which issued to Logan et al. on Dec. 3, 1996, discloses a separating apparatus for the cooling system of a marine engine. It describes an apparatus for separating solid material from cooling water in the cooling system of a marine engine. The apparatus includes a hollow member or housing having an inlet to receive cooling water and having an outlet. A drain opening is located in the housing above the bottom surface of the housing and is connected through a suitable conduit to a temperature responsive drain valve. A generally J-shaped tubular member is disposed in the housing and has one end connected to the drain outlet while a second end is slightly above the bottom surface of the housing out of alignment with the inlet. When the drain valve is open, water will drain through the housing to the drain outlet while solid debris will collect in the bottom of the housing beneath the second end of the tubular member.
U.S. Pat. No. 5,664,526, which issued to Logan et al. on Sep. 9, 1997, discloses an apparatus for separating solid material from cooling block water in a marine engine block. An apparatus for separating solid material from cooling water in the cooling system of the engine block of a marine engine is described. The engine block comprises a plurality of cylinder bores surrounded by a cooling passage through which cooling water is pumped. The bottom portion of the block includes a drain outlet that communicates with the cooling passage and a tubular separating member that has a first generally horizontal section that is sealed within the drain outlet. The tubular separator also includes a second section that is located within the cooling passage and extends downwardly from the inner end of the first section and is located between two adjacent cylinder bores. The lower end of the second section is closed and a port is provided in the side of the second section adjacent the closed end and facing toward one of the cylinder bores. The outer end of the first section of the tubular member, which is located on the exterior of the block, is connected through a suitable hose or conduit to an automatic drain valve which is located at a level beneath the engine block. When the ambient temperature falls beneath a selected value, the drain valve will open and water will drain from the engine block through the tubular separator to the drain valve, while solid debris will collect in the bottom of the cooling passage beneath the level of the port to prevent the debris from contacting the temperature responsive valve.
U.S. Pat. No. 6,004,175, which issued to McCoy on Dec. 21, 1999, discloses a flush valve which uses only one moving component. A ball is used to seal either a first or second inlet when the other inlet is used to cause water to flow through the valve. The valve allows freshwater to be introduced into a second inlet in order to remove residue and debris from the cooling system of the marine propulsion engine. When freshwater is introduced into a second inlet, the ball seals the first inlet and causes the freshwater to flow through the engine cooling system. When in normal use, water flow through the first inlet and seals the second inlet by causing the ball to move against a ball seal at the second inlet. Optionally, a stationary sealing device can be provided within the second inlet and a bypass channel can be provided to allow water to flow pass the ball when the ball is moved against the ball seat at the first inlet. This minimal flow of water is provided to allow lubrication for the sea water pump impeller if the sea water pump is operated during the flushing operation in contradiction to recommended procedure.
U.S. Pat. No. 6,033,272, which issued to Whiteside on Mar. 7, 2000, describes a marine jet drive system with a debris cleanout feature. A marine jet propulsion system for a boat or the like comprises a power plant for rotating a driveshaft. A gear system is connected to the driveshaft and is configured to engage and rotate an impeller shaft. A clutch system is provided for selectively causing the impeller shaft to alternatively be engaged by one or the other of ring gears and thereby selectively rotating the impeller in opposite directions. By this arrangement, rotation of the impeller in a first direction draws water through the housing in normal fashion to provide thrust at the exit opening while rotation of the impeller in the opposite direction reverses the flow through the housing and causes debris to be flushed out of the impeller or inlet opening.
U.S. Pat. No. 6,506,085, which issued to Casey et al. on Jan. 14, 2003, discloses a pump and drain apparatus for a marine propulsion system. An integral pump and drain apparatus is contained in a common housing structure to reduce the required space needed for these components in the vicinity proximate the engine of a marine propulsion system. The valve of the drain is remotely actuated by air pressure and therefore does not require the boat operator to manually remove plugs or manually actuate mechanical components to cause the engine to drain through a drain conduit that is formed as an integral part of the housing structure.
U.S. Pat. No. 7,005,077, which issued to Brenner et al. on Feb. 26, 2006, describes a shipboard human waste treatment for removing solids. A method and system for separating human waste solids from liquid for a shipboard toilet system that allows for the separation of solid waste, compaction of the solid waste and storage of solid waste is described. Wastes are deposited into a shipboard toilet system that uses vacuum toilets to flush waste into a large inclined solid waste separating tank. A vacuum pump is attached to the separation tank to maintain negative pressure within the tank and system to move the separated liquid stream. The separation tank has a separating screen disposed across its entire width to retain solid wastes while allowing liquid to flow through. After separation from liquids, solid waste material is compacted and dewatered with a helical screw through an inclined tube, and packaged for later removal as landfill or burned in the ship incinerator.
U.S. Pat. No. 7,108,782, which issued to Higgins et al. on Sep. 19, 2006, describes a marine vessel on board wastewater treatment system. Shipboard wastewater undergoes treatment within an automatic system based on membrane bioreactor technology. Using selective control established through an operator interface, the system can be operated under automatic process/standby mode or maintenance mode and sludge concentrate can be directed either overboard, to an onboard storage tank or to undergo further treatment within an concentration device or destruction within an incinerator for example depending on the ship's equipment, location and operating conditions.
U.S. Pat. No. 7,128,027, which issued to Straub et al. on Oct. 31, 2006, discloses a cooling system for an outboard motor. A cooling system of an outboard motor provides back and forth flow of water from one side of an exhaust passage to the opposite side in order to avoid the creation of stagnant pools of water within which minerals and debris can collect. This result is accomplished by causing the cooling water to flow back and forth from one side of the exhaust passage to the other so that all portions of the water passages are forced to conduct water through them at a relatively high velocity. A water reservoir is formed between an exhaust conduit and an oil reservoir in order to reduce the operating temperature of the oil within the reservoir.
The patents described above are hereby expressly incorporated by reference in the description of the present invention.
Although some outboard motors utilize filtering devices and related techniques to avoid the intake of debris through the cooling system of its engine, some types of debris can bypass them and be conducted through the cooling system. As these materials, such as soil and sand, pass through the engine cooling system, they can collect in the lower regions of some of the containment portions of the cooling system. As the debris accumulates in the lower portions of various containers, some drain openings can possibly be blocked. Usually the drain openings that become blocked in this way are intended to function in a manner that allows water to drain out of the system in order to avoid damage that can be caused when accumulated water freezes. These situations are particularly troublesome because the engine can appear to be operating normally even though the small drain openings are completely blocked. Water can be drawn into the cooling system, directed through the engine water jacket, conducted into a temporary reservoir which allows other components to be cooled by the water, and through a pickup conduit that then directs the water back to the body of water. These operations can be performed in a way that appears normal even though a drain opening in the temporary holding container is completely blocked. The problem may only appear at some later time when the accumulated water within that temporary holding container is subjected to freezing temperatures. Those freezing temperatures can create ice within the cooling system and the expansion of the ice can create severe damage. It would therefore be significantly beneficial if the normal operation of the marine propulsion device could remove debris from the region of the drain openings so that the ice is not formed at a later time. It would be particularly beneficial if the normal operation of the outboard motor could keep the region clean in the area surrounding the drain opening without any additional effort required by the operator. It would also be significantly beneficial if the system could allow an easy cleanout procedure so that debris can be removed from regions that are not close to the drain openings, but are in other portions of the bottom regions of the reservoir.